User Defined Type (Int32 Enum) in abstract class raises InvalidCastException

Scenario:

I have defined an abstract entity called Lookup which has an id type of int and 3 fields,

ItemKey (String <= 100)
ItemValue (String)
LookupType (User Defined Type of LookupTypes Enum)

I then created an entity called Country that derives from the Lookup entity and defines a "Derived Association" from Country to Lookup with a Discriminator Name of "LookupType" and a value of 1 which is the value of the LookupTypes.Country enum item.

When trying to Find or Add, (or I imagine any operation), on the Country entity I get the following error:

Invalid cast from 'System.Int32' to 'LSBOProto.Business.Models.LookupTypes'

This is directing towards an MS SQL 2008 DB

Another thing that I tried to do is define the Discriminator Value of LookupTypes.Country hoping that it would use that but it doesn't like that as it can't use the enum value in the attribute so I had to use the value.

Also, on a side note, I originally used a property name of "Key" and although it created the database correctly, when trying to access the DB it complained about the field name and raised a SQL Client Exception.

Thanks,

Jim

This issue is not to do with the abstract class, but rather to do with the use of the field as a discriminator.  We currently have a limitation where the discriminator must be an Int32 -- it cannot be an enum.  To work around this, define LookupType as an Int32.  You can make it private so that app code can't poke bad values in there.  If app code needs to access the LookupType as an enum, then add the following (in the partial class if you are using the designer):

public LookupTypes LookupTypeCode {
  get { return (LookupTypes)(this.LookupType); }
}

Thanks for letting us know about the issue with the property name "Key" -- we'll look into it.